#ifndef __SPHERE_INCLUDE
#define __SPHERE_INCLUDE

#include "circle.h"

/**
  Class which implements a Sphere
 */
class Sphere : public Circle {
    public:
        /** Pass-through constructor that invokes Circle(radius) */
        Sphere(int r) : Circle(r) {};
        
        /** Overriden from Circle.  Prints the area of the sphere. */
        void area();
        
        /** Overriden from Circle.  No-op as spheres are 3D. */
        void perimeter();
        
        /** Overriden from Circle.  Prints the volume of the sphere. */
        void volume();
};

#endif